Safety-fuse



A. S. BALDWIN.

SAFETY FUSE.

APPLICATION FILED mmz, x917.

1,31: 1,67%. Patented July 29 1919.

WITNESSE5. INVENTOR.

.y 7 M Y :2? 5% 45am ATTORNEYS.

ARTHUR S. BALDWIN, 0F BALTIMORE, MARYLAND.

SAFETY-FUSE.

Specification of Letters Patent.

Patented July 29, 1919.

Application filed March 2, 1917. Serial No. 151,904.

To all whom it may concern.

Be it known that I, ARTHUR S. BALDWIN, a citizen of the United States, residing at Baltimore, in the State of'Maryland, have invented certain new and useful Improvement-s in Safety-Fuses, of which the following is a specification.

This invention relates to improvement in safety fuses for shells or'projectiles, and is particularly an improvement in that class of fuses known as inertia-operated fuses in which the firing pin is normally held in a safety position and is designed to become armed only when'the shell or projectile is fired from a gun.

The present invention has for an object to provide improved plunger means normally held separated by a firing pin and the separated plunger devices in turn maintaining the firing pin in a safety position.

Another object of the invention is to provide a plunger and firing pin mechanism for a fuse wherein the plunger of a plurality of normally separated parts may become closed together when subjected to the shock offiring, and at the same time, place the firing pin in an armed position so that the combined weight, of the plunger parts may be placed in readiness-to move forward, carrying the'firing pin :with them to detonate the primer upon impact of the shell or projectile.

A further object is to provide improved constructions whereby the use of shear pins between the fuse stock or casing and the plunger parts may be avoided, so that all liability'offriction of the burred edges, caused by the shearing of the parts, between the stock creasing chamber-wall and the plunger parts, will be avoided, and the movement of the detonating parts in said chamber will be unrestricted upon impact of the'shell or projectile.

The invention is illustrated in the accompanying drawing, wherein,

Figure 1, shows a longitudinal section through a fuse structure embodying the invention, the parts being shown'in the unarmed or safety condition.

F ig; 2,. illustrates another longitudinal section through a fuse structure embodying thevinvention in a slightly modified form.

Fig.6, shows anotherlongitudinal section through a fuse device in which the invention is shown instill a slightly difierent" form."

Fig. 4, illustrates in longitudinal section another embodiment of the inventive idea, the parts also being in a safety or unarmed position,-and

Fig. 5, through the same,'the section-being taken on the line 55 of Fig. 4.

Referring to Fig, 1, of the drawing the numeral 6, designates the case orstock havmg exterior screw-threads 7, by which the fuse may be attached to the shell'or projectile, and also having an interior-circular chamber 8, extendinglongitudinally therein with a flat end wall 9, at the outer end of said chamber. chamber is closedby a cap body 10, in which a primer 11, is-located, and said cap, in the present instance, has a short passage 12, extending between the primer and an additional powder charge 13. In the present instance, the cap also has an annular channel 14, at the side confronting the case or stock chamber 8, for a purpose that will hereinafter be explained.

On the interior of the chamber 8, I provide a plunger comprising a plug section 15,

and a socket section 16, respectively. The plug section has a base portion 17,0f a diameter to fit the interior of the chamber and also has a plug portion 18, of a reduced diameter that extends from the-base portion toward that end of thechamber where the primer is located. The reduced plug portion also has a central recess 19, extending longitudinally therein for a purpose which will also presently be explained.

The plunger socket-section 16', has a socket portion 20, at that end which confronts the plug section which socket is of a diameter to receive the plug-portion and telescopically 'engagethe latter. An annular wall 21, of

the socket section depends between the wall of the case or stock chamber and the wall of the plug portion and has a beveled lower edge 22.

In the form of device illustrated in Fig; 1, of the drawing the beveled edge22, of the socket section is provided so as to enter and rivet into an annular undercut 23, in the base of the plug portion, when theset-back, due

to the shock of firing from a gun, takes place.

The socket section 16, has a centralpassage 24, extending downwardly from its upper end which opensinto an enlarged passage25,

The inner end of the stock-' 27, is seated loosely in of the plug section and a reduced stem 28, pro ects upwardly from the upper end of the post and passes through the enlarged passage 25, in the socket section and enters the smaller central passage 2st, of the latter. The upper end 29, of the reduced stem forms the firing pin and while it is held in alinement with the primer 11, it is maintained in said passage 2%, below the primer by means which will now be eX- plained.

By providing a reduced stem 28, an annular shoulder 30, is formed around the base thereof and the upper end of the cylindrical post 27, and a washer plate 31, is seated under the annular depression 26, of the socket section while the shoulder 30, on the post is seated under the washer consequently the washer plate serves to hold the socket section 16, up under the cap-body 10, and at the same time keep the post 27, seated in the recess of the plug portion.

It will thus be understood that the washer plate 31, keeps the plug and socket sections of the plunger separated and at opposite ends of the stock chamber and at the same time prevents the post, 27 and stem 28, from forwardly toward the primer. Thus devices in as clearly moving the washer keeps all of the firing the safety ,or unarmed condition, shown in Fig. 1, of the drawing.

The washer plate is formed of a material that will withstand any ordinary or accidental shock to which the fuse might be subjected during handling or shipment but will be punctured or sheared by the set-back of the socket-section 16, during the considerable shock of firing from a gun-the portion cut from the washer by the post being driven into the passage 25,'as the latter enters said passage upon the set-back operation, and the firing pin end 29, thereby being projected from the inner end of passage 24, and'thus becoming armed.

During the set-back of the socket section, the beveled edge 22, thereof will enter the undercut 23, ,on the plug portion and thereby become engaged by contracting around the undercut thus uniting the socket and plug sections, and clamping the post 27, between them, so that the combined weight of both sections, as well as the weight of' the post, may be utilized in the forward plunge of the parts toward the primer upon impact of the shell or projectile;

An annular groove 32, is provided in the upper or inner end of the socket section so that a coiled spring 33, may be seated in the annular channel 14, of the cap and in said groove 32, whichspring will distend when the socket section moves back to armed posiclaim and desire tion and aid in holding said plunger parts in the set-back position and prevent them creeping forward during the flight of the shell and before impact of the later.

The structure disclosed in Fig. 2, of the drawing differs from that in Fig. 1, only in so far as the engagement of the plug and socket sections of the plunger is concerned. In this structure the inner end of the socket 20, has an outward flaring annular groove 34:, while the inner end of the plug is provided with an annular beveled lip 35-the groove and lip "being so related that upon the set back they will be driven together with sufficient force to cause the lip to expand outwardly into the annular groove and thereby lock the plug and socket sections together.

In the form shown in Fig. 3, of the drawing the plug and socket sections of the plunger are simply, telescopically engaged and the locking-together features are entirely omitted-the coiled spring 33, being depended upon to prevent creeping ,or forward movement of the plunger parts after' the set-back operation has taken place.

The fuse shown in Figs. & and 5, differs from those in Figs. 1 and 2, in the form of device employed to hold the socket and plug together when in the set-back position. In

this structure the wall of the socket is provided with an annular groove 36, while the plug section has a semi-circular slot 37, in which a semi-circular bolt 38, is loosely placed. When the set-back takes place in this structure by the shock of projection and the shell is rotated as it leaves the gun, due to the rifling in the gun barrel, the centrifugal action will cause the loose semi-circular bolt 38, to move outwardly and enter the groove 36, in the socket wall which at 1 that time will be in register with the plug slot 37.

In all of the. forms, the plunger is constructed of a plug section and a socket section, and the post and firing pin eXtends through the normally separated sections and keeps them separated by means of the interiorly located washer plate. Also in all the forms the post and pin serve to retain the washer plate in position between the separated plunger parts in that the reduced stem 28, extends through a perforation in the washer plate and the shoulder 30, of the post seats against the outer or under side of said plate.

'Having'described my invention what I to secure by United States Letters Patent is- 1. In a fuse device the combination with a case having a chamber therein, of an explosive element; a plunger having a plug section with a recess therein and a socket section with a passage therein; a firing pin in said plug recess and socket passage, and means between the firing pin and one of said sections for normally holding the plug and socket sections separated.

2. In a fuse device the combination with a case having a chamber therein, of an expLosive element; a plunger having a plug section and a socket section the socket section having connecting passages of difierent diameters; a plate interposed between the plug section and the larger of the socketsection passages and a firing pin having one end seated against the plug section and provided with a reduced stem that extends through said plate into said passage of the socket section whereby to hold the two sections in a separated condition.

3. In a fuse device for shells or projectiles the combination with a case or stock having a chamber therein, of a plunger in said chamber and having a plug part and a socket part with a passage extending from the socket to one end; a firing pin having one end in said passage and its other end in the plug part of the plunger and rupturable means engaging the firing pin and the' said socket part of the plunger to hold the plunger parts separated and to retain the firing pin in an unarmed position.

' In testimony whereof I afiiX my signature in the presence of two witnesses.

ARTHUR S. BALDl/VIN.

Witnesses:

C. E. WILDER, A. R. HENRIEM.

Copies 01' this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

